Input-output weight distribution of terminated RSC codes with limited codelength

In this paper, we evaluate the input-parity weight distribution of terminated recursive systematic convolutional (RSC) codes. On the trellis of convolutional codes, the paths are ended at any state of the code after information sequence input. The number of paths ended at the zero-state can be described by the number of error events which can easily be obtained. For the paths at non-zero state of the code after information sequence input, we equivalent the input-parity weight distribution of these paths to input-parity weight distribution of some sets of error events. Using the number of weight distribution that have ended at each of the states, we provide the input-parity weight distribution of terminated RSC codes. Our algorithm provides input-parity weight distributions for all input weights and it is a precise result for terminated RSC codes that is necessary for the performance analysis of code.